As a special case of the general question - “What information can be obtained about the dimension of a subset of by looking at its orthogonal projections into hyperplanes?” - we construct a Cantor set in each of whose projections into 2-planes is 1-dimensional. We also consider projections of Cantor sets in whose images contain open sets, expanding on a result of Borsuk.
@article{bwmeta1.element.bwnjournal-article-fmv144i2p119bwm,
author = {John Cobb},
title = {Raising dimension under all projections},
journal = {Fundamenta Mathematicae},
volume = {144},
year = {1994},
pages = {119-128},
zbl = {0821.54020},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-fmv144i2p119bwm}
}
Cobb, John. Raising dimension under all projections. Fundamenta Mathematicae, Tome 144 (1994) pp. 119-128. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-fmv144i2p119bwm/
[00000] [B] K. Borsuk, An example of a simple arc in space whose projection in every plane has interior points, Fund. Math. 34 (1947), 272-277. | Zbl 0032.31404
[00001] [E] R. Engelking, Dimension Theory, PWN, Warszawa, and North-Holland, Amsterdam, 1978.
[00002] [M] S. Mardešić, Compact subsets of and dimension of their projections, Proc. Amer. Math. Soc. 41 (2) (1973), 631-633. | Zbl 0272.54030
[00003] [R] Referee's comment